[PATCH 6.1 36/82] cifs: account for primary channel in the interface list

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

6.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Shyam Prasad N <sprasad@microsoft.com>

[ Upstream commit fa1d0508bdd4a68c5e40f85f635712af8c12f180 ]

The refcounting of server interfaces should account
for the primary channel too. Although this is not
strictly necessary, doing so will account for the primary
channel in DebugData.

Cc: stable@vger.kernel.org
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/smb/client/sess.c    | 28 ++++++++++++++++++++++++++++
 fs/smb/client/smb2ops.c |  6 ++++++
 2 files changed, 34 insertions(+)

diff --git a/fs/smb/client/sess.c b/fs/smb/client/sess.c
index 33e724545c5b4..634035bcb9347 100644
--- a/fs/smb/client/sess.c
+++ b/fs/smb/client/sess.c
@@ -288,6 +288,7 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 	struct cifs_server_iface *iface = NULL;
 	struct cifs_server_iface *old_iface = NULL;
 	struct cifs_server_iface *last_iface = NULL;
+	struct sockaddr_storage ss;
 	int rc = 0;
 
 	spin_lock(&ses->chan_lock);
@@ -306,6 +307,10 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 	}
 	spin_unlock(&ses->chan_lock);
 
+	spin_lock(&server->srv_lock);
+	ss = server->dstaddr;
+	spin_unlock(&server->srv_lock);
+
 	spin_lock(&ses->iface_lock);
 	if (!ses->iface_count) {
 		spin_unlock(&ses->iface_lock);
@@ -319,6 +324,16 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 
 	/* then look for a new one */
 	list_for_each_entry(iface, &ses->iface_list, iface_head) {
+		if (!chan_index) {
+			/* if we're trying to get the updated iface for primary channel */
+			if (!cifs_match_ipaddr((struct sockaddr *) &ss,
+					       (struct sockaddr *) &iface->sockaddr))
+				continue;
+
+			kref_get(&iface->refcount);
+			break;
+		}
+
 		/* do not mix rdma and non-rdma interfaces */
 		if (iface->rdma_capable != server->rdma)
 			continue;
@@ -345,6 +360,13 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 		cifs_dbg(FYI, "unable to find a suitable iface\n");
 	}
 
+	if (!chan_index && !iface) {
+		cifs_dbg(FYI, "unable to get the interface matching: %pIS\n",
+			 &ss);
+		spin_unlock(&ses->iface_lock);
+		return 0;
+	}
+
 	/* now drop the ref to the current iface */
 	if (old_iface && iface) {
 		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
@@ -367,6 +389,12 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 			old_iface->weight_fulfilled--;
 
 		kref_put(&old_iface->refcount, release_iface);
+	} else if (!chan_index) {
+		/* special case: update interface for primary channel */
+		cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
+			 &iface->sockaddr);
+		iface->num_channels++;
+		iface->weight_fulfilled++;
 	} else {
 		WARN_ON(!iface);
 		cifs_dbg(FYI, "adding new iface: %pIS\n", &iface->sockaddr);
diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 2c1898803279a..4cc56e4695fbc 100644
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -752,6 +752,7 @@ SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon, bool in_
 	unsigned int ret_data_len = 0;
 	struct network_interface_info_ioctl_rsp *out_buf = NULL;
 	struct cifs_ses *ses = tcon->ses;
+	struct TCP_Server_Info *pserver;
 
 	/* do not query too frequently */
 	if (ses->iface_last_update &&
@@ -776,6 +777,11 @@ SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon, bool in_
 	if (rc)
 		goto out;
 
+	/* check if iface is still active */
+	pserver = ses->chans[0].server;
+	if (pserver && !cifs_chan_is_iface_active(ses, pserver))
+		cifs_chan_update_iface(ses, pserver);
+
 out:
 	kfree(out_buf);
 	return rc;
-- 
2.42.0